Harness-stitching machine



Dec. 21 1926.

M. G'. BLISS HARNESS ,(sTITcHlNG MACHINE Fild Nov. 1,0l '192:4 5Sheets-Sheet l Dec. 21

, M. G. BLISS HARNESS ST'ITCHING MACHINE Filed Nov. 10y 1924 3Sheets-Shet 2 9i, A @a .95

Dec. 21 1926. 1,611809 M. G. BLISS HARNESS STITCHING MACHINE Filed Nov.10y 1924 3 Sheets-Sheet 3 l W /wlB/anr. 77.-? '3?' am? ,ufr

Patented vDec. 2l, 1926'.

UNITED sTA-TI-:s

PATENT OFFICE.

MALCOLM G. BLISS, YOFINORTH GRAFTON, MVASSACHJ'SETTS,` ASSIGNOR TOHEYWOOD BOOT & SHOE COMPANY, F WORCESTER, MASSACHUSETTS, A CORPORATIONOE MASSACHUSETTS.

HARNESS-STITCHING MACIN E.

Applicationled November 10, 19,24. Serial No. 748,866.

This invention relates to sewin machines of the type used in stitching soes, luggage, and other articles formed of leather or of similarmaterial. It,l is sometimes desirable to produce stitching which willclosely resemble hand sewing, such as is found, for instance, in handmade harnesses.

This :so-called harness stitch has been herctofore produced mechanicallyto a limited i0 extent by impressing or indenting each' stitch after itis formed by the sewing machine needle and shuttle. rlhe mechanismprovided has been greatly limited in utility, as it would only indentstitches disposed in substantially straight lines and could not be usedfor indenting stitches for shoemaking or for other purposes where abruptor short curves abound.

It is the object of my invention to rovide a stitching machine by whicha arness stitch may be produced mechanicallyu in either straight orcurved lines and vparticularly in curves of very short radius.

To the attainment of this object, a par- 2* ticular feat-ure of myinvention relates to the provision of means for swinging the indentingmember in one direction or the other to correspond with thecurvature ofthe line of stitching.

Another object of the invention'is to provide means by which the feedwill be varied as the line of stitching curves to the right or to theleft, in such a manner as to provide a substantially uniform stitchingand indenting space for either straight or curved stitching.

` My invention further relates to arrangements and combinations of partswhich will be hereinafter described and more particularly pointed out inthe'appended claims.

A preferred form of the invention is shown in the drawings, in whichFig. 1 is a 'i'ront elevation of my improved harness stitching machine;

Fig. 2 is a detail plan View, looking in the direction of the arrow 2 inFig. 1;

Fig. 3 is a detail sectional elevation, taken along the line 3 3 in Fig.1;

Fig. 4 is an enlarged front elevation of V certain parts of thestitching and indenting mechanism;

along the line 8-8 in Fig. 4; 6" Fig. 9 is a sectional side elevation,taken along the line 9-9 in Fig. 4;

Figs. 10 and 11 are partial sectional side elevations, taken along thelines 10-10 and 11--11 in Fig. l; a5

Figz l2 is a plan View of the thread lubricatlng device; I Fig. 13 is aside elevation thereof partly 1n section;

Fig. 14 is a detail sectional plan view, 70 taken along the line 14--14in Fig. 4, and

Fig. 15 shows a sample of the Work which l may be produced by myimproved machine.

t Referring to the drawings, I have shown a sewing machine which in manyof its 75 features is of a yusual commericial type. This machinecomprises a frame mounted upon a base 21 suitably secured to a table orother support 22. A needle 23 is clamped in the lower end of a needlebar 24 which au is vertically reciprocated by a link 25 pivoted on acrank pin 26 secured at the end of the main driving shaft I27. -Theshaft 27 extends Athrough the-,upper portion of the frame 20 and isprovided with a 85 pulley 28 which may be .driven by a belt- 29 from anysuitable source of power.

The thread 'l passes from. a suitable guide or support 30 to alubricating device 31 from which it is guided through an eye e0 32, afriction device 33 and a stitch tensioning device 34 to the needle 23.lNith the exception of the lubricating device, these parts may be of anyusual construction.

rlhe lubricatingdevice is shown in de- @a tail in Figs. 12 and 13 andcomprises a receptacle 35 for oil or lubricant. The thread enters thetop ot the receptacle, pass sing downward through the lubricant to theloop or guide 36, and upward between fricico tion discs 37 and 38, whichdiscs are preferably faced with felt or other caishion material and maybe adjusted toward or from each other bya screw 39. These-friction discsserve to wipe any surplus lubricant from the thread as it is drawnbetween the discs. The upper disc 38 is preferably provided with anL-shaped slot 40 (Fig. 12) through which the thread is guided.

For producing .the eiect of a harness stitch, I have provided anindenting device or stitch separator which I will now describe. Thisindenting device comprises a plunger 45 (Fig. 5) slidable in a bearingracket 46 which is clamped to the needle bar 24 by a set screw 47 (Fig.4). lA pin 48 (Fig. 5) in the side of the plunger 45 is slidable ina'slot 49 in the bracket or bearing 46 and acts to p-revent relativeangular movement o the plunger in its bearing and also as a stop tolimit downward movementy thereof. J

A coil spring 50 is inserted in the bearing 46 and presses the plunger45 yieldingly downward to engage the work. The

plunger 45 is provided on its lower surface' mechanism by which thisangular move.

ment is produced will now'be described.

The needle bar 24 is provided at its upper end with a collar 52 securedthereto and having two grooves 53 (Fig. 14) formed therein. Thesegrooves 53 form guide-ways for a pair of plates or guidebars 54 mountedona support 55 (Fig. 6.) having an annular groove 56 therein. Thesupport is supported upon an upper arm 57 (Fig. 4) of the frame 20 andis rotatable thereon in a circular recess in a plate 58.

Retaining devices 59 extend into the annular groove 56 and preventdisplacement of the support 55. The support 55 and guide bars 54 arethus mounted for angular movement about the axis of the needle bar 24and when thus moved they cause a corresponding angular movement vof theneedle bar and indenting device, while at the same time the needle baris freely slidable vertically between the guide-bars 54;

An arm 60 (Fig. 4) is fixed on a rock shaft 61 and is slotted at itsouter end as indicated at 62 (Fig. 7) to receive a ball 63 mounted on astud 64 clamped to a plate 65 secured to the upper end of a post orstandard 66 projecting upward from the angularly movable support 55. Asthe rock shaft 61 and arm 60 are moved angularly, a correspondingangular movement of the guide-bars 54 will occur.

T o permit the angularl movement of the needle bar while at the sametime maintaining driving connection therewith, I have devised a specialconnection between the driving link 25 and -the needle bar 24. For thispurpose I have pivoted the link 25 on a stud 70 projecting laterallyfrom-a collar 71 which is loose on the needle bar 24. A member' 72projects upward from the collar 71 and has a yoke-73, the arms of whichproject into a lsegmental annular opening or 90 groove 74 in a collar 75 which is secured to the needle bar 24 by a binding screw 76. Thecollar-71 is,thus connected to reciprocate the needle bar while at thesame time a considerable range of relative angular 95 j movement ispermitted. j

The rock shaft 61 is provided with an arm (Fig. 11) having a ball andsocket connecti-on'81 to a connecting rod 82. The

lower end of the rod 82 (Fig. 1) has a 9 similar connection to an arm 83(Figs. 1 and 2) mounted on a control shaft 84 which is supported inbearings 85 dn the table 22. An arm 86 projects downward from the shaft84 and supports a cross bar 87. Collars 88 are adjustably secured to thecross bar 87 and are provided with depending rods 89 on which knee pads90 are adjustably secured. By pressing upon one or the other of the knee.pads 90, the shaft 84 will be rocked in a corresponding direction andthis will in turn cause similar angular movement of the rock shaft 61and theneedle bar 24.

It is desirable that the rock shaft and needle bar be yieldinglymaintained in normal position when there is no pressure upon the kneepads. For this purpose I providearms 91 and 92 (Fig. 2) enga ed bycompression springsA 93 and thus yielcglingly restored to the positionshown in Fig. 2, after manual displacement in either direction.

As a further means for holding the rock shaft 66 yieldingly in normalosition, I have provided a cam plate 95 (Fig. 9) having a iatsurface 96,engaged by a block 97 mounted on a spring arm 98 secured to a fixedportion of the machine frame 20. A flat spring 99 is also secured to theframe 20 and carries an adjusting screw 100 by which increased pressuremay be applied to the block 96. If the rock shaft 61 is turned angularlyin either direction, the cam 95 25 will force the block 97 outward andthe pressure of the spring plate 98 and 99 will act to restore the cam95 andv shaft 61 tok normal position, whenever the manual pressure onthe knee pads is removed.

. The shutt-le 101 (Fig. 5) is substantially teintes of the usualoscillating type, except that certain of the parts are made right handinstead of left hand.

By the mechanism thus far described, l am able to swing the needle barand indenting device angularly at the will of the operator so that theindenting device will be aligned with the needle holes when the machineis stitching shortJ curves, such as are indicated in lFig. l5. lin thisway the indentations are formed exactly in the needle openings insteadof being thrown out of line, aI condition which occurs when the needlebar and indenting device are fixedin angular position.,

This feature of my invention is of great value and is essential to theproduction of an etlicient harness stitching machine to be used oncurved lines of stitching.

l have found, morever, that the length of the stitch'is not constantwhen stitching around short curves.. lf the curvature is in onedirection, the stitches are much closer together, and if the curvatureis in the opposite direction, the stitches are much further apart. Forsatisfactory work, it is necessary that all of the stitches besubstantially equal in spacing and accordingly l have provided mechanismfor increasing or decreasing the feed in accordance with the directionof curvature, so that the above described variation in spacing may becounteracted and a substantially uniform spacing will result.

For this purpose, l have provided the rock shaft 0l with an additionalarm 105 (Fig. 10) supporting a rod 106 having a ball and socketconnection with a link 107, similary connected to a bell crank lever108,

mounted on a fixed pivot 109, and connected by al link to the usual feedfork lll. B v these connections the feed fork will be raised or loweredas the rock shaft 61 is moved angularlyin one direction or the other.rlhis vertical adjustment of the feed fork ,causes an increase ordecrease in the feed in the usual manner through well known connectionsnot shown in the drawings.

With this additional attachment, l am able not onlyto keep my indentingor separating device in line with the needle openings but l can alsocounteract the variations in spacing which otherwise occur in stitchingaround -short curves'and I am thus able to produce harness stitchingeither in straight wise than as set forth in the claims, but what l doclaim is l. A harness stitching machine, comprising a frame, a needlebar mounted to reciprocate therein, a stitch separating device, mountedto reciprocate with said needle bar, and controllingr means to vmovesaid separating device transversely to its path of reciprocation.V

2. A harness stitching machine, comprising a frame, a needle bar mountedto reciprocate therein, a stitch separating device and means to movesaid stitch separating device angularly about the axis of said needlebar. I

3. A harness stitching machine,compris ing a frame, a needle bar mountedto reciprocate therein, a stitch separating device, and means to movesaid' needle bar and separating device angularly about the axis of saidneedle bar.

4. A harness stitching machine, comprising a frame, a needle bar mountedto reciprocate therein, va stitch separating device acting upon thestitches after formation by the needle and means to move said stitchsepara-ting device angularly about the anis of said needle bar.

5. A'harness stitching machine, comprising a frame, a needle bar mountedto reciprocate therein, a stitch Aseparating device, means controlled bythe operator effective to move said separating device about its support,and -means to yieldingly restoresaid separating device to its normalposition when said controlled means is released.

8. A harness stitching machine comprising a frame, a work feedingmechanism, a stitch-forming mechanism, a stitch separating device, andmeans to simultaneously change the relative position of said separatingdevice in respect to said frame and to vary the action of the feedingmechanism.

9. A harness stitching machine comprising a frame, a work feedingmechanism, a stitch-forming mechanism, a stitch separating device, meansto move said separating device angularly about its support and toincrease the feed as said device is moved angularly in one direction.

Dit

10. A harne'ss stitching machine comprising a frame, a Work` 'feedingmechanism, aI

stitch-forming mechanism, a stitch-separating device, means to move saidseparating device angularly about its-support and 'to decrease the feedas saidvdeviceiis moved angularl)r in one direction.

11. A harness stitchingmachine compris ing a rame,a work 'feedingmechanism, a. stitch-forming mechanism, a stitch-separatand controllingmeans to move said separating device transversely' to its path ofreciprocation, said controlling means includinnr a rock shaft, a camlate fixed thereto, anc

a spring plate yiel ingly engaging a flat face on said cam plate torestore said shaft to normal position.

inga frame, a `needle bar mounted to' reclprocate therein, a 4stitchseparating device mounted to reciprocate with said'needle bar,

13. A harness stitching' machine compris-l and controlling means to movesaid separating. device transversely to its-path of reciprocation', saldcontrolling means including a rock shaft and a pair of opposed springsacting ,.to

yieldingly restore' said substantiallynormal position.

shaft to 14. In a sewing machine, angularly ad-` justable stitchingmechanism, feeding mechanismadjustable therewith, including manual'control means'to vary'the length of the feed in accordance with changesin the amount= and direction of curvature of the line of stitching. A

15. In a sewing machine, 'angularly ad-v justable stitching mechanism,feeding mechanism, and means to increase'thc length of 'f the feedas thestitching curves in one direction and to decrease the length ofA .thefeed as. the stitching curves 'the opposite di'-,

rection.

In testimony whereof `I have hereunto l affixed my signature.

MALCOLM G. BLISS.

